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प्रश्न
Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.
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उत्तर
In the presence of conc. acids such as H3PO4 and H2SO4 alcohols undergo dehydration to yield alkenes.
\[\ce{\underset{Ethanol}{H3C - CH2 - OH} ->[conc{.} H+/Delta] \underset{Ethene}{CH2 = CH2} + H2O}\]
The mechanism for this reaction is:
Protonation of ethanol (Step 1):
Formation of carbocation (Step 2):
Formation of ethene and regeneration of proton (Step 3):
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संबंधित प्रश्न
Write the mechanism of the following reaction :
Give the equation of the following reaction:
Treating phenol with chloroform in the presence of aqueous NaOH.
When 3-methylbutan-2-ol is treated with HBr, the following reaction takes place:
\[\begin{array}{cc}
\phantom{...................................}\ce{Br}\\
\phantom{..................................}|\\
\ce{CH3 - CH - CH - CH3 ->[HBr] CH3 - C - CH2 - CH3}\\
|\phantom{.........}|\phantom{...................................}|\phantom{...........}\\
\ce{CH3}\phantom{...}\ce{OH}\phantom{...............................}\ce{CH3}\phantom{.......}\\
\end{array}\]
Give a mechanism for this reaction.
(Hint: The secondary carbocation formed in step II rearranges to a more
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Lucas reagent is ____________.
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(i) H2/Pd
(ii) LiAlH4
(iii) NaBH4
(iv) Reaction with RMgX followed by hydrolysis
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\[\ce{CH3CH2OH}\] can be converted into \[\ce{CH3CHO}\] by ______.
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- \[\ce{CH3CH2CH(OH)CH3}\]
- \[\ce{(C2H5)3COH}\]
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What is Lucas reagent?
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Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.
Write the mechanism of acid dehydration of ethanol to yield ethene.
